Read it through once

Then Joshua began his terrible raid, and from Jericho clear to this Baal-Gad, he swept the land like the Genius of Destruction. He slaughtered the people, laid waste their soil, and razed their cities to the ground. He wasted thirty-one kings also. One may call it that, though really it can hardly be called wasting them, because there were always plenty of kings in those days, and to spare. At any rate, he destroyed thirty-one kings, and divided up their realms among his Israelites. He divided up this valley stretched out here before us, and so it was once Jewish territory. The Jews have long since disappeared from it, however.